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Following Farhan's mention of my frequency counters... http://www.hanssummers.com/electronics/equipment/radiofreqcounter/intro.htm this one is a full 8-digit counter. On the other hand, you can

No problem! My favourite varicap is a standard 5mm red LED. Have a look at my 30m QRSS beacon project http://www.hanssummers.com/radio/qrss/index.htm which used one for the frequency shifting to

Hello again Chris, If you want to follow the "from scrap" route, you'd better use 8.86 MHz crystals from defunct color TV sets or the 14.318 MHz ones from old and/or defunct PC motherboards...

Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the BITX20 group. File : /K7HKL/BITX20 FREQUENCY CALCULATION SPREADSHEET.xls

Hi Twisting the wires together for winding trifilar inductors is made easier with a simple tool built for that purpose. A picture of my "Trifilar Twister Tool" is attached to this email. A copy of

Hi All What a great idea ... wish I had thought of it my self -- a bit more control than using an electric drill !! Charles G4VSZ

Nice one Arv! Now we're on the subject I'll share my own method and experiences in case it helps anyone. I don't have available nice new spools of wire labelled 28 or 32 swg. I do have a junk

Hans When working with really small wire (ie. you don't have anything better to work with!) try twisting two or even three conductors together and use this as one wire to wind your toroid coils.

Hi In converting the BITX20 design for building my BITX40 transceiver I found myself 'experimenting' with several different sets of air-core toroid inductors. Soldering, removing, & re-soldering

OK, those are cute. And way cool, ESPECIALLY the parallel LC config that uses the cap's legs for termination and mounting. I love this place. Jim N6OTQ

Hi, This is indeed a good idea. I have a question - basic becuse I'm very new to this field! I noticed that some of the turns are closely wound while some are not. How does this affect the

Bharat The turns on that coil were sloppy because I got tired of winding them. There are 150 turns of #42 wire on that coil. While it does work at about the intended inductance I would probably be

Has anyone measured the Q of the toriods? I wondered whether it mattered too much provided the winding details were observed. However care has to be taken with the coating materials. There is an

Hi Since Farhan's stated original intent in designing the BITX20 was to provide an inexpensive transceiver, maybe it would be appropriate to show BITX builders an inexpensive way to measure unmarked

Very Nice, thanks very much :-) Regards, John ============================================= email: k5jhf@... photos: http://photos.yahoo.com/k5jhf@... files:

Thanks, Arv. 73s ----- Bharat D Balsavar VU2BDX

Hi PC Board material that is stored for some time usually takes on a layer of oxidation that hinders soldering components to its surface. In the past I have routinely used sandpaper to remove this

Hi Can I also suggest that where the components are to be placed that the PCB pad is tinned and where earth connections are to be made that area too is tinned, as it ensures a good joint and the joint

I'd like to suggest the use of a copper/silver cleaner, such as Tarn-X. I don't know what would be similar across the pond or in other parts of the world. I just pour a little bit of Tarn-X on a

Thanks a million, Monty, Great job. And thanks to Arv Evans for sharing this circuit :-) Regards, John ============================================= email: k5jhf@... photos: